Such devices are used for inductive charging of a rechargeable battery incorporated in an electric vehicle. In this case a primary coil unit is provided at a charging station which is brought close to a secondary coil unit arranged on the vehicle for charging of the vehicle battery so that the inductive transmission of power is made possible from a primary coil contained in the primary coil unit to a secondary coil contained in the secondary coil unit. The primary coil unit of a charging station is ordinarily arranged on the ground of a vehicle parking area or recessed into the ground, and the secondary coil unit is mounted on the bottom of an electric vehicle.
The primary coil unit of a charging station can be exposed to a high mechanical load when a vehicle inadvertently rides onto or over it with a wheel when entering or leaving the charging station. This should not lead to damage or destruction of the primary coil unit. Although the secondary coil unit in an electric vehicle is potentially less vulnerable to being mechanically loaded, this is also not ruled out, for example, when driving over a bump or an object lying on a roadway. Neither the coil of a coil unit, nor sensors that can be arranged in a coil unit for its monitoring, nor ferrite elements that are ordinarily contained in a coil unit for magnetic flux guidance are designed to withstand high mechanical loads.